The Biostatistics and Information Technology Facility (BIT) of the University of Chicago Cancer Research Center (UCCRC) provides collaborative statistical and database development support to UCCRC investigators engaged in clinical, basic, and population science research. These services include collaboration on study design, development of database/information management systems, and statistical analysis for phase I, phase II, and phase III clinical trials; assistance in the design, database construction, and analysis of retrospective and prospective observational studies; and statistical collaboration on basic science and animal research projects. Clarification and refinement of hypotheses to be tested, specification of outcome variables, determination of appropriate sample-sizes, development of data analysis plans, statistical analysis, and assistance in the preparation of manuscripts for publication are major areas of activity. BIT members also participate in teaching activities and engage in methodological research in support of projects conducted within the UCCRC. The BIT interacts closely with the Protocol and Data Management Office to ensure a high level of data quality and analysis for clinical trials conducted by UCCRC investigators. BIT faculty serve key roles on the two Protocol Review and Monitoring System committees (i.e., the Clinical Trials Review Committee and the Accrual Monitoring Committee) thus ensuring that the biostatistical sections of protocols are rigorously reviewed and that patient accrual is evaluated, in part, as a function of projected versus actual accrual numbers. Finally, close collaboration with the Biological Sciences Division's (BSD) Information Services department will facilitate integration of UCCRC database and data tracking systems with BSD and hospital-wide information systems.